1. Field of the Invention
The present invention relates to a suspension, a head suspension assembly, and a disk drive apparatus that contribute to an increase in record and playback reliability.
2. Description of the Prior Art
In a hard disk drive (HDD) apparatus using a magnetic disk as a recording medium, record and playback is performed with a head slider not contacting the magnetic disk, by energizing the head slider, on which a head performing record and playback is mounted, toward the magnetic disk and using air flowing between the head slider and magnetic disk in conjunction with rotation of the magnetic disk, like bearings.
Typically, a head slider x1 is supported by a head suspension assembly (HSA) x2 shown in FIG. 2, and is energized toward the disk side by being loaded in the extent of, for example, 2 grams by the spring x3.
Because of the requirement for acceleration of seek speed and the like, lightening of the HSA x2 is desired while keeping its predetermined stiffness. For this reason, HSAs x2 that keep their stiffness by ribs x2b that are provided on both sides of the arm part x2a are commonly used.
Large capacity and acceleration of HDDs is also desirable due to recent performance advances of information processors. Therefore, it becomes necessary to decrease the space between disks, to increase rotational speed, and to increase the density of track pitches (TPI). Under these conditions, the influence of a mechanical resonance system on reliability and performance of an HDD becomes drastically large.
Along with an increase of the disk rotational speed or decrease of the space between disks, the airflow rate in the HDD becomes higher. If the airflow rate becomes higher, however, the influence of resonance generated in the HSA by the airflow cannot be disregarded.
If the airflow at high speed in laminar flow hits the rib of the HSA, a so-called Karman vortex street occurs in the downstream side of the rib, and the alternating force caused by this vortex street excites the vibration of the HSA to make the servo unstable.
An example of an apparatus solving this problem is a magnetic head suspension unit disclosed in Published Unexamined Patent Application No. 5-174507. This magnetic head suspension unit suppresses the occurrence of an eddy flow by making each rib have a cross-section of a laminar airfoil. Furthermore, a position where a boundary layer, where speed is sharply dropped due to viscosity near a surface of the airfoil, is exfoliated from the surface of the airfoil is retracted by making each rib hollow and providing pores in the surface of the rib while making the edge of the rib open. In addition, a plurality of pores lighten the unit.
Nevertheless, the magnetic head suspension unit disclosed in the Published Unexamined Patent Application No. 5-174507 has complicated construction. Therefore, the unit has a problem that production of the unit is difficult, and hence production cost becomes expensive.
The present invention is performed in consideration of the above problems, and provides a suspension, a head suspension assembly, and a disk drive apparatus that can have stable servo, and contribute to cost reduction owing to easy production.
A suspension according to the present invention comprises an arm part where a mounting part for mounting a head slider is formed at an edge thereof, a standing part that is provided along the longitudinal direction of the arm part and is provided for keeping stiffness of the arm part, and openings that are provided in the standing part having 10% or more of an opening ratio.
In addition, another suspension according to the present invention comprises an arm part where a mounting part for mounting a head slider is formed at an edge thereof, and a standing part provided along the longitudinal direction of the arm part at height approximately five times higher than the plate thickness of the arm part or less and is provided for keeping stiffness of the arm part.
Furthermore, still another suspension according to the present invention comprises an arm part where a mounting part for mounting a head slider is formed at an edge thereof, and a box part that is provided near the center of the arm part along the longitudinal direction of the arm part and is provided for keeping stiffness of the arm part.